Apparatus for applying getters to lamp filament supports



April 28, 1953 p v o r 2,636,472

APPARATUS FOR APPLYING GETTERS TO LAMP FILAMENT SUPPORTS Filed Feb. 28. 1952 Invendrovs: Paul, Var go Thomas A. Fos ter, Jr. 36 b5 The'n- Attorne Patented Apr. 28, 1953 APPARATUS FOR APPLYING GETTERS TO LAMP FILAMENT SUPPORTS Paul Vargo, Lyndhurst, and Thomas A. Foster,

Jr., Cleveland, Ohio, assignors to General Electric Company, a corporation of New York Application February 28, 1952, Serial No. 273,936 7 Claims. (01. 118-221) Our invention relates to apparatus for manufacturing electric incandescent lamps and other electrical devices and, more particularly to apparatus for automatically applying a chemical clean-up agent or getter in the form of a paste to the parts of the filament mount of incandescent lamps and other electrical devices. The clean-up agents, or getters, react under the heat of operation of the electrical device to absorb or transform into non-injurious materials those contaminating materials which remain in said devices after they have been exhausted and sealed.

One object of our inventionis to provide apparatus for automatically applying a measured amount of a getter in paste form to specific portions of the leading-in wires of a filament mount of an electric device. The apparatus is adaptable to operation at one work station of an automatic machine for making the filament mounts, and is capable of operation without attention for relatively extended periods.

Another object of our invention is to provide improved apparatus which will obviate the deficiencies of prior gettering apparatus by effecty ing the transfer of getter by means of a notched metal finger and by causing said metal finger to pass along a definite portion of the leading-in wire. Apparatus heretofore employed provided for the getter to be carried to the mount by means of a brush which required frequent cleaning in order to retain its operating efliciency. The brush lost resiliency and form very shortly after being placed in operation because of the quick drying properties of the getter and was soon covered by a 'dry residue. The proper dosage, thickness of getter coating or position of the coating could not be maintained under these conditions.

Further advantages of apparatus comprising our invention is that it provides a convenient means of applying getter to more than one leading-in wire of a mount at the same time, and it is suited to the application of getter to different portions of the leading-in wires at the same time. The apparatus also avoids the application of heavy concentrations or blobs of the getter which may not operate efiectively, and it further avoids the spilling over of getter onto the ends ofthe filament which is very likely to be injurious thereto. I

Still other features and advantages of our invention will appear from the following description of a species thereof and from the drawing.

In the drawing, Fig. 1 is a perspective view of gettering apparatus comprising our invention in the course of applying getter to a plurality of leading-in wires extending to the two filaments of a mount; Fig. 2 is a perspective view of a getter-applying arm of said apparatus on a larger scale and showing the opposite side of said arm from that appearing in Fig. 1; Fig. 3 is a perspective view of the operating means of the gettering'apparatus on a smaller scale than Fig.

lamp thereto at regular intervals. As shown,

the apparatus is located at operative relation to the jaws l--2 and the locating plate 3 of a' head of a carrier advancing the mount 4 laterally to and beyond the position shown. The gettering apparatus is mounted at a fixed position on a table 5 located below and surrounding the carrier which may be, for instance, of the type included in the automatic mount making machine disclosed in Illingworth Patent 1,733,881 dated October 29, 1929. Also included in the combination is a drive shaft 6 located below the table 5 and turning through one revolution while each mount 4 remains before the gettering apparatus, as is also the usual manner of operating mountmaking apparatus.

Each cycle of operation of the gettering apparatus effects the transfer of a quantity of getter to the mount 4 by the swinging movements of an arm 1 which carry it horizontally back and forth between a spoon 8, containing a small quantity of the semi-fluid getter 9 contained within the reservoir I0, and the mount 4. The swinging movement of the arm I, which is comprised of the hub portion 5 l and the extending rod portion I2, results from a corresponding rotation of the vertical shaft l3 holding said hub portion H and is brought about by operating means located below the table 5 and'engaging the end of the shaft I3 extending beyond the base [4. The back, or getter pick-up swing, of the arm 1, which initiates the cycle of operation, is 'the result of rotation of a high portion of the cam l5 of the operating means into engagement with the roller It on the bell crank I! and the resulting rocking or turning movement of said bell crank I! about the pivot screw IS in a bracket [9 depending from the lower surface of the table 5. A connecting rod 20 transfers the motion of the bell crank ll, which occurs against the tension of the return spring H, to the arm 2! clamped to said shaft IS. The forward, or getter-delivery swing, of the arm 1 follows the reception of getter by the metal fingers 22 and 23 on the cap 24 at the end of the rod portion l2 of the arm 1.

The getter carrying fingers 22 and 23, as shown particularly in Fig. 4, extend from essentially radial slots in the cap 24 and, at the time of 3 their engagement with the mount are positioned somewhat below (about 30 degrees) the horizontal. "The back swing of the arm 1, however, causes the fingers 22 and 23 to be rotated about the axis of said arm I to a downwardly inclined position where their ends are able. to dip into the getter pool in the spoon 8. This rotation is eifected when the tab 25 on the rod portion l2 strikes the stationary cam 2% so that it is pushed to a trailing position with respect thereto. The tab 25 is fixed on the rod portion 12 and, in moving as described, turns said rod portion i2- in the hub portion H against the twisting resist- 'ance of a torsion spring 21 located thereabout and with respective ends attached to the tab 25 and within an opening inthe cap nut- 28. The externally threaded cap nut 28 is screwed tightly into the hub portion 1! at a position to hold the enlarged end of the rod portion !2 therein by shouldered engagement therewith and does not rotate with respect to the hub portion H; During the back swing. of the arm '5, the tab 25 slides along the bottom'suriace of the arcuate cam 2t; which is supportedby the standard29, and the fingers 22 and 23 are at a posi tion (Fig. 4) below and on the opposite side of a vertical plane through the axis of the arm l" which causes the ends thereof to be at the same elevation and which therefore allows them to be wet equally by a pool of getter.

The getter is applied to the ends of the fingers 22 and 23 by a vertical movement of spoon t which carries said spoon 8 from within the main supply of getter in the reservoir 52 to a raised position where said ends are immersed in the 1" getter pool therein. :This manner of supplying the. getter fingers 22 and 23 assures application thereto of getter of a uniform consistency, and is brought about by thecorrespondingmovements of the vertical rod 3% to which said spoon 8 is attached by means of an inverted U -shaped strap 3! and the clamp block 32. The operating means, located below the table and the support standard 33 for the rod 30, provides for the vertical motion of said rod 39 by oscillation 2G and said fingers 22 and 23 are turned back to the position shown in Figs. 1 and 2 by the uncoiling of the spring 21. The rotation of the rod portion l2 of the arm I turns the fingers 22 and 23 90 degrees around the axis of said arm l to the position where they are located at subof. the operating lever at about a pin in the sta- 4 tionary bracket 35 in accordance with the advance of differently shaped portions of the cam 35 on shaft s into engagement with the roller 37. A helical spring 38; extending between the end of the operatinglever 34 and a partof table 5 (not shown) causes said lever 34 to follow the contour of the cam 36. As shownrthe form of the cam is such that the spoon!) is out of the reservoir I?) only for the moment required to allow the getter to wet the fingers 22 and 2,3, and; is immediately plunged back. into the reservoir This manner of operation retards the drying and consequent thickening of the get-'- ter as much as possible and constantly stirs and agitates the full getter supply so that a very uniform mixture thereof is always available. Further agitation of the getter supply is provided by a steady stream of air bubbles passed upward therethrough from a pipe 39 extending to a point near the bottom of the reservoir l0 and connected to an air supply through flexible hose to.

The, return swing of the arm I which moves the getter fingers 22 and 23 to, operative relation to the mount 4 causes the tab 25 to slide back along the cam 26 without causing said fingers 22 and 23 to change their relation in said arm I. At the termination of the swing, however, the tab 25 passes beyond the end of the cam v stantially thirty degrees to the horizontal and where their ends are in the vertical plane of the leads @3- and 44. At the completion of the movement, the radially extending pin M in the rod portion l2 bears against the stop pin 42 in the. cap nut 28. Because the fingers 22 and 23 are of d fierent length and are offset circumferentially around the arm 1, the ends of said fingers 22 and 23 take difierent positions along said leads 43 and 44 which positions are at uniform distances from the filaments 45 and 48 held by said. leads t3 and M. In the usual manner of, operating the apparatus the ends, of the fingers 22 and partially encompassbut donot' contact the leads 43 and 44.; however, a variation in the position thereof may cause one or both of-said loads 23 and 44 to be contacted by said fingers 22 and 23 but otherwise not to be harmed since the angular position of said fingers 22 and 23 and the slight pressure of the spring 2-! permits them to swing back. The ends of the fingers 22 and 23 lie in a vertical plane corresponding to the plane of the leads 43 and as at the time the getter is applied and accordingly will dip to equal depth into the getter pool in the, spoon 8 if the rod portion l2 oi the arm 5 is turned back ninety degrees, as is the degree of movement thereof in this particular instance. Notches in the ends of the fingers 22 and 23 permit them to carry a sufiicient supply of getter and also permit the fingers 22 and 23' to extend part way around the leads 43 and 44.

Completion of the gettering operation is. effected by a short upward movement of the arm 3 which carries the getter fingers 22 and 23 up along the leads 43 and M. This motion of the fingers 22 and 23 spreads the getter more thinly over the leads 43 and 4G and avoids the formation of blobs and heavy concentrations thereof heretofore obtained with other types of apparatus. The upward wiping action of the arm 6 results when the shaft I3 is moved correspondingly by the operating means and in particular by the operating lever 4'? under the infiuence of cam 42 and roller 49. The operating lever 4! turns about the fixed shaft 5!}. and forces the shaft i3 upward against the compression resistance of the helical spring 5| located about the portion of the shaft l3. between the arm 2i and the-table '5. The return downward movement of the arm 1 does not-occur until the arm is backed away from the mount 4and another mount l is indexed into place by the carrier.

Although a preferred embodiment of our invention has been disclosed, it will be understood that the invention is not to be limited to the specific construction and arrangement of parts shown, but, that they may be widely modified within the spirit and scope of our invention as defined-in the appended claims.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. Apparatus for applying a getter paste to a lead wire of a mount comprising means for holding the mount at a work station, means for supplying a pool of the getter paste at a position adjacent said work station, an arm having an axially rotatable end portion and movable between the getter supplying means and the work station, a finger having a notched end extending laterally from the rotatable end portion of the arm, and means for rotating the rotatable end portion of the arm during the said movement thereof to cause the notched end of the finger to be immersed in the getter pool at one terminus of its motion and to cause the notched end to take a position about a portion of the said lead wire at the other terminus of said motion.

2. Apparatus for applying a getter paste to a lead wire of a mount comprising means for holding the mount with a lead wire thereof extending vertically at a work station, means for supplying a pool of getter paste at a position adjacent said work station, an arm having an axially rotatable end portion and movable through a horizontal plane between the getter supplying means and the work station, a finger having a notched end extending laterally from the rotatable end of the arm, and means for turning the rotatable end portion of the arm during the movement thereof to cause the notched end of the finger to extend downward from said arm and be immersed in the getter pool at one terminus of the motion thereof and to cause said notched end to extend approximately horizontally and take a position about a portion of the said lead wire at the other terzninus of said motion.

3. Apparatus for applying a getter paste to a lead wire of a mount comprising means for holding the mount with a lead wire thereof ex tending vertically at a work station, means for supplying a pool of getter paste at a position adjacent sale work station, an arm having an axially rotatable end portion and movable through a horizontal plane between the getter supplying means and the work station, a finger having a notched end extending laterally from the rotatable end of the arm, means for rotating the rotatable end portion of the arm during the movement thereof to cause the notched end of the finger to extend downward from said arm and be immersed in the getter pool at one terminus of the motion thereof and to cause said notched end to extend approximately horizontally, and take a position about a portion of the said lead wire at the other terminus of said motion, and means for moving the arm vertically at the work station to cause the notched end of the finger to wipe along a portion of the lead wire.

l. Apparatus for applying a getter paste to a lead wire or" a mount comprising means for holding the mount at a work station, a main supply reservoir for the getter paste at a position adjacent the work station, an arm having an axially rotatable end portion and movable between positions over the getter reservoir and the work station, a finger having a notched end extending laterally from the rotatable end portion of the arm, a spoon for lifting a quantity of the getter paste to a position above the reservoir, and means for rotating the rotatable end portion of the arm during the movement thereof to cause the notched end of the finger to be immersed in the getter paste in said spoon at one terminus of the motion and to cause the notched end to take a position about a portion of said lead Wire at the other terminus of said motion.

5. Apparatus for applying a getter paste to spaced lead Wires of a mount comprising means for holding the mount with the leads at a definite position at a work station, means for supplying a pool of getter paste at a position adjacent said work station, an arm having an axially rotatable end portion movable between the getter supply means and the work station, a pair of fingers having notched ends and extending laterally from the rotatable end portion of the arm in spaced relation corresponding to the spacing of the said lead wires, and means for rotating the rotatable end portion of the arm during the movement thereof to cause the notched ends of the fingers to be immersed in the getter pool at one terminus of the motion and to cause the notched ends to take positions about respective lead wires at the other terminus of said motion.

6. Apparatus for applying a getter paste to spaced lead wires of a mount comprising means for holding the mount with the lead wires at a definite position at a work station, means for supplying a pool of getter paste at a position adjacent said work station, an arm having an axially rotatable end portion movable between the getter supply means and the work station, a pair of fingers having notched ends and extending substantially in a radial direction from the end portion of said arm and spaced apart both longitudinally and circumferentially along said arm, and means for rotating the said rotatable end portion of the arm during the movement thereof to cause the notched ends of the fingers to be immersed in the getter pool at one terminus of the motion and to cause the notched ends to take positions about respective lead wires of the mount at the other terminus of said motion.

'7. Apparatus for applying a getter paste to spaced lead wires of a mount comprising means for holding the mount with the lead wires thereof extending vertically at a work station, a main supply reservoir for the getter paste at a position adjacent the work station, an arm having an axially rotatable end portion and movable through a horizontal plane between positions over the getter reservoir and the work station, a pair of fingers having notched ends and extending substantially in a radial direction from the end portion of said arm and spaced apart both longitudinally and circumferentially along said end portion of the arm, a spoon for lifting a quantity of the getter paste to a position above the reservoir, and means for rotating the rotatable end portion of the arm during the movement thereof to cause the notched ends of the fingers to extend essentially downward from said arm and be immersed in the getter paste from the quantity in the spoon at one terminus of the motion and to cause the notched ends to extend approximately horizontally and take vertically spaced positions about respective lead wires of the mount at the other terminus of said motion.

PAUL VARGO. THOMAS A. FOSTER, JR.

References Cited in the file of this patent UNITED STATES PATENTS Number 

